Quick way to add Bump node
Activate the Node Wrangler Addon.

With the sphere unwrap

Click on add material with the selected default material just change the diffuse material to Principled BSDF.

Before u go to next step u must save the image with the name (normal, spec, Ambient, disp.) Note : without name it will not work so just the normal name should be to the images so that addon find out correctly.

With the Principled BSDF Node Selected Press Ctrl+Shift+T

A window target select the file which are saved with the name

Click ok and render